Android example source code file (DdmHandleHeap.java)

This example Android source code file (DdmHandleHeap.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, bytebuffer, chunk, chunk_hpgc, chunk_hpif, chunk_nhsg, chunk_real, ddmhandleheap, heap, hpsg, io, os, recent, runtimeexception, string, unsupportedoperationexception, util, utilities, utils, vm

The DdmHandleHeap.java Android example source code

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.ddm;

import org.apache.harmony.dalvik.ddmc.Chunk;
import org.apache.harmony.dalvik.ddmc.ChunkHandler;
import org.apache.harmony.dalvik.ddmc.DdmServer;
import org.apache.harmony.dalvik.ddmc.DdmVmInternal;
import android.os.Debug;
import android.util.Config;
import android.util.Log;
import java.io.IOException;
import java.nio.ByteBuffer;

/**
 * Handle native and virtual heap requests.
 */
public class DdmHandleHeap extends ChunkHandler {

    public static final int CHUNK_HPIF = type("HPIF");
    public static final int CHUNK_HPSG = type("HPSG");
    public static final int CHUNK_HPDU = type("HPDU");
    public static final int CHUNK_HPDS = type("HPDS");
    public static final int CHUNK_NHSG = type("NHSG");
    public static final int CHUNK_HPGC = type("HPGC");
    public static final int CHUNK_REAE = type("REAE");
    public static final int CHUNK_REAQ = type("REAQ");
    public static final int CHUNK_REAL = type("REAL");

    private static DdmHandleHeap mInstance = new DdmHandleHeap();


    /* singleton, do not instantiate */
    private DdmHandleHeap() {}

    /**
     * Register for the messages we're interested in.
     */
    public static void register() {
        DdmServer.registerHandler(CHUNK_HPIF, mInstance);
        DdmServer.registerHandler(CHUNK_HPSG, mInstance);
        DdmServer.registerHandler(CHUNK_HPDU, mInstance);
        DdmServer.registerHandler(CHUNK_HPDS, mInstance);
        DdmServer.registerHandler(CHUNK_NHSG, mInstance);
        DdmServer.registerHandler(CHUNK_HPGC, mInstance);
        DdmServer.registerHandler(CHUNK_REAE, mInstance);
        DdmServer.registerHandler(CHUNK_REAQ, mInstance);
        DdmServer.registerHandler(CHUNK_REAL, mInstance);
    }

    /**
     * Called when the DDM server connects.  The handler is allowed to
     * send messages to the server.
     */
    public void connected() {}

    /**
     * Called when the DDM server disconnects.  Can be used to disable
     * periodic transmissions or clean up saved state.
     */
    public void disconnected() {}

    /**
     * Handle a chunk of data.
     */
    public Chunk handleChunk(Chunk request) {
        if (Config.LOGV)
            Log.v("ddm-heap", "Handling " + name(request.type) + " chunk");
        int type = request.type;

        if (type == CHUNK_HPIF) {
            return handleHPIF(request);
        } else if (type == CHUNK_HPSG) {
            return handleHPSGNHSG(request, false);
        } else if (type == CHUNK_HPDU) {
            return handleHPDU(request);
        } else if (type == CHUNK_HPDS) {
            return handleHPDS(request);
        } else if (type == CHUNK_NHSG) {
            return handleHPSGNHSG(request, true);
        } else if (type == CHUNK_HPGC) {
            return handleHPGC(request);
        } else if (type == CHUNK_REAE) {
            return handleREAE(request);
        } else if (type == CHUNK_REAQ) {
            return handleREAQ(request);
        } else if (type == CHUNK_REAL) {
            return handleREAL(request);
        } else {
            throw new RuntimeException("Unknown packet "
                + ChunkHandler.name(type));
        }
    }

    /*
     * Handle a "HeaP InFo" request.
     */
    private Chunk handleHPIF(Chunk request) {
        ByteBuffer in = wrapChunk(request);

        int when = in.get();
        if (Config.LOGV)
            Log.v("ddm-heap", "Heap segment enable: when=" + when);

        boolean ok = DdmVmInternal.heapInfoNotify(when);
        if (!ok) {
            return createFailChunk(1, "Unsupported HPIF what");
        } else {
            return null;        // empty response
        }
    }

    /*
     * Handle a "HeaP SeGment" or "Native Heap SeGment" request.
     */
    private Chunk handleHPSGNHSG(Chunk request, boolean isNative) {
        ByteBuffer in = wrapChunk(request);

        int when = in.get();
        int what = in.get();
        if (Config.LOGV)
            Log.v("ddm-heap", "Heap segment enable: when=" + when
                + ", what=" + what + ", isNative=" + isNative);

        boolean ok = DdmVmInternal.heapSegmentNotify(when, what, isNative);
        if (!ok) {
            return createFailChunk(1, "Unsupported HPSG what/when");
        } else {
            // TODO: if "when" is non-zero and we want to see a dump
            //       right away, initiate a GC.
            return null;        // empty response
        }
    }

    /*
     * Handle a "HeaP DUmp" request.
     *
     * This currently just returns a result code.  We could pull up
     * the entire contents of the file and return them, but hprof dump
     * files can be a few megabytes.
     */
    private Chunk handleHPDU(Chunk request) {
        ByteBuffer in = wrapChunk(request);
        byte result;

        /* get the filename for the output file */
        int len = in.getInt();
        String fileName = getString(in, len);
        if (Config.LOGD)
            Log.d("ddm-heap", "Heap dump: file='" + fileName + "'");

        try {
            Debug.dumpHprofData(fileName);
            result = 0;
        } catch (UnsupportedOperationException uoe) {
            Log.w("ddm-heap", "hprof dumps not supported in this VM");
            result = -1;
        } catch (IOException ioe) {
            result = -1;
        } catch (RuntimeException re) {
            result = -1;
        }

        /* create a non-empty reply so the handler fires on completion */
        byte[] reply = { result };
        return new Chunk(CHUNK_HPDU, reply, 0, reply.length);
    }

    /*
     * Handle a "HeaP Dump Streaming" request.
     *
     * This tells the VM to create a heap dump and send it directly to
     * DDMS.  The dumps are large enough that we don't want to copy the
     * data into a byte[] and send it from here.
     */
    private Chunk handleHPDS(Chunk request) {
        ByteBuffer in = wrapChunk(request);
        byte result;

        /* get the filename for the output file */
        if (Config.LOGD)
            Log.d("ddm-heap", "Heap dump: [DDMS]");

        String failMsg = null;
        try {
            Debug.dumpHprofDataDdms();
        } catch (UnsupportedOperationException uoe) {
            failMsg = "hprof dumps not supported in this VM";
        } catch (RuntimeException re) {
            failMsg = "Exception: " + re.getMessage();
        }

        if (failMsg != null) {
            Log.w("ddm-heap", failMsg);
            return createFailChunk(1, failMsg);
        } else {
            return null;
        }
    }

    /*
     * Handle a "HeaP Garbage Collection" request.
     */
    private Chunk handleHPGC(Chunk request) {
        //ByteBuffer in = wrapChunk(request);

        if (Config.LOGD)
            Log.d("ddm-heap", "Heap GC request");
        System.gc();

        return null;        // empty response
    }

    /*
     * Handle a "REcent Allocation Enable" request.
     */
    private Chunk handleREAE(Chunk request) {
        ByteBuffer in = wrapChunk(request);
        boolean enable;

        enable = (in.get() != 0);

        if (Config.LOGD)
            Log.d("ddm-heap", "Recent allocation enable request: " + enable);

        DdmVmInternal.enableRecentAllocations(enable);

        return null;        // empty response
    }

    /*
     * Handle a "REcent Allocation Query" request.
     */
    private Chunk handleREAQ(Chunk request) {
        //ByteBuffer in = wrapChunk(request);

        byte[] reply = new byte[1];
        reply[0] = DdmVmInternal.getRecentAllocationStatus() ? (byte)1 :(byte)0;
        return new Chunk(CHUNK_REAQ, reply, 0, reply.length);
    }

    /*
     * Handle a "REcent ALlocations" request.
     */
    private Chunk handleREAL(Chunk request) {
        //ByteBuffer in = wrapChunk(request);

        if (Config.LOGD)
            Log.d("ddm-heap", "Recent allocations request");

        /* generate the reply in a ready-to-go format */
        byte[] reply = DdmVmInternal.getRecentAllocations();
        return new Chunk(CHUNK_REAL, reply, 0, reply.length);
    }
}